The present invention relates to a temperature controlled pipe and a method of manufacturing same, and, more particularly to a pipe that can be heated.
When crude oil, gas, or other similar fluids are transported through pipes and/or risers in subsea environments, several challenges are presented with respect to designing the pipes and risers for transporting the fluids. For example, the pipes and risers must provide a fluid barrier while being resistant to collapse and penetration yet must be flexible and connectable to other equipment. Also, the temperature of the fluid flowing the pipe often must be maintained above a minimum value to insure that the conveyed fluid flows freely. For example, when the conveyed fluid is primarily methane, moisture present in the gas can form methane hydrate when the pressure is sufficient and the temperature is not sufficiently high. These, hydrates build locally and tend to clog the pipe. Also, when the conveyed fluid is crude oil with an excessive amount of wax dissolved in the oil, wax can build up on the walls of the pipe, which leads to a decreased flow in the pipe and associated oil production.
Therefore, several attempts have been made to heat flexible pipes, such as by wrapping an electric heater wire around the pipe or embedding such a wire in a layer of the pipe. However, these arrangements are less than optimum since, in general, the compositions of the various layers of pipe are not good conductors of the heat or electrical current.
The embodiments of the present invention overcome these deficiencies.